The lamination process of high pressure laminate cabinets is an important process in lamination molding. high pressure laminate cabinets are laminated with impregnated adhesive tape in two polished metal templates, placed in a hot press, heated and pressurized between the two layers. After curing by hot press, it is cooled and demolded.

I. Laminating equipment

The main equipment is the hot press set. Auxiliary equipment are loading and unloading machine, template rotary machine, template cleaning machine, laying mold cleaning machine (stacking machine) and other equipment. The production combination is divided into single hot pressing and cooling machine and two hot pressing and cooling machines.

There are 2 types of hot presses currently in use: open type pressing hot press and closed vacuum hot press. Compared with open type hot presses, vacuum hot presses have two outstanding advantages.
(i) the forming unit pressure is 1/2-1/3 lower, i.e., the flow of glue is reduced, the warp and weft of the cloth move less, the internal stress of the laminate is reduced, and the warpage is finally reduced.
② It can avoid bubbles inside the board and at the edges, and the quality of the product is higher; vacuum hot pressing is more and more widely used in composite molding.

The performance and control level of the hot press directly affect the quality of the product, and also have a direct relationship with the molding process. The hot press mainly controls the temperature field and pressure of the heating plate.

1. Heating plate

The structure of the heating plate and the thermal medium used directly affect the uniformity of the temperature field of the heating plate, the uniformity of the temperature of the plate surface, the uniformity of the melting of the adhesive tape, and the discharge of the gas and air between the adhesive tape layers after gluing. Therefore, the heating plate should be heated up quickly and evenly, and the temperature difference on the plate surface should be less than 3℃.

There are two kinds of heating plate channels: single-in single-out and double-in double-out. The latter is complicated to manufacture, piping is also complicated, high cost, and generally rarely used. The former uses steam heating, the temperature difference between the plate surface is large (about 5 ℃); when using hot water or heat-conducting oil, the temperature difference between the plate surface is less than 3 ℃; using heat-conducting oil is more effective because the pressure of heat-conducting oil is low (less than 0.5 MPa) and the temperature is high (up to about 300 ℃).


For the temperature control of the whole machine, the general hot press opening is 12-20, so that the heating plate presents the temperature gradient from bottom to top. Steam heating for a single point of total control more, the gradient is about 5 ℃ or so. Hot water or heat-conducting oil is generally zoned (generally divided into 2-3 zones) control, the temperature gradient is just a control error of less than 3 ℃, which is conducive to the same pressure, the top, middle and bottom of the same curing speed, which is conducive to improving product quality.

2. Pressure

At present, most of the hot presses use hydraulic presses, which can meet the unit pressure required for product molding up to 12.5MPa, and the pressure stability is less than ±500KPa, which can be set according to the process requirements. The tonnage of multi-layer press is generally larger, usually 2000-3000t.

High pressure laminate cabinets lamination process

1. Tape cutting and matching

Tape cutting is to cut the tape into a certain size (according to the size of the press), the cutting equipment can be continuous fixed-length slicer, or manual cutting. The size of the tape must be accurate, not too long or too short. The cut tape is neatly stacked, and the different adhesive content and fluidity of the tape are stacked separately and marked for storage. In order to avoid as much as possible the increase of volatile parts and the decrease of soluble resin content, the tape should be stored in a dry room.

The cutting method of different usage of laminate is also different: the laminate used for lamination is cut according to the production specification, while leaving a margin for processing raw edges; the laminate used for tape winding is first cut into the tape required for winding, and then lapped by sewing, rewound, and rolled into a certain diameter tape tray for use.

2. Hot pressing process of high pressure laminate cabinets

The combination of the loading cart is pushed into the middle of the hot plate of the multi-layer press, and the hot plate slowly rises and closes and is pressed with steam under pressure.

The key to the pressing process is to determine the process parameters, the most important of which are temperature, pressure and time. The pressure regime depends firstly on the variety and nature of the material, and secondly on the thickness of the product, plate area and equipment conditions.